我们正在使用Oracle数据库构建WPF应用程序,同时使用NHibernate和uNHAddins扩展。在DataGrid中,我们尝试从表中获取值,使用此查询LINQ:
return (from f in rFConsumption.GetAll()
let d = f.CounterDtm
where f.CounterDtm >= dataHoraInicio && f.CounterDtm <= dataHoraFim
group f by (d.Year - 2000) * 384 + d.Month * 32 + d.Day into g
select new RFConsumption
{
COGCounter1 = (g.Sum(f => f.COGCounter1)),
BFCounter1 = (g.Sum(f => f.BFCounter1)),
NatGasCounter1 = (g.Sum(f => f.NatGasCounter1)),
MixGasCounter1 = (g.Sum(f => f.MixGasCounter1)),
COGCounter2 = (g.Sum(f => f.COGCounter2)),
BFCounter2 = (g.Sum(f => f.BFCounter2)),
NatGasCounter2 = (g.Sum(f => f.NatGasCounter2)),
MixGasCounter2 = (g.Sum(f => f.MixGasCounter2)),
COGCounter3 = (g.Sum(f => f.COGCounter3)),
BFCounter3 = (g.Sum(f => f.BFCounter3)),
NatGasCounter3 = (g.Sum(f => f.NatGasCounter3)),
MixGasCounter3 = (g.Sum(f => f.MixGasCounter3)),
}
).ToList<RFConsumption>();
所以,我的问题是:
答案 0 :(得分:1)
您可以使用NHibernate以多种方式编写相同的查询,对我来说最有趣的是NHibernate QueryOver&lt;&gt;。 因此,如果您的查询工作正常,则此查询应该有效:
return Session.QueryOver<rFConsumption>()
.Where( fc => (fc.CounterDtm >= dataHoraInicio && fc.CounterDtm <= dataHoraFim))
.SelectList(list => list
.SelectGroup(f => ((f.CounterDtm.Year - 2000) * 384 + f.CounterDtm.Month * 32 + f.CounterDtm.Day)) //use group by
.Select(exp =>
new RFConsumption() //here you define the return data type based on your specified group
{
// exp[0] represents the data returned and grouped by the above statements, so here you can reform it to fit into the form of your new entity
// exp[0] here will be equivilant to g in your query
})
.OrderBy( ee => ee.COGCounter1 ) //order by any of the properties of RFConsumption
.ToList<RFConsumption>();
您应首先添加实体RFConsumption:
public calss RFConsumption
{
public int COGCounter1 { get; set; }
public int BFCounter { get; set; }
....
}